build(deps): bump third_party/yaml-cpp from 94710bb to 96f5c88

Bumps [third_party/yaml-cpp](https://github.com/jbeder/yaml-cpp) from `94710bb` to `96f5c88`.
- [Release notes](https://github.com/jbeder/yaml-cpp/releases)
- [Commits](jbeder/yaml-cpp@94710bb...96f5c88)

---
updated-dependencies:
- dependency-name: third_party/yaml-cpp
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>